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<p class="level0"><a name="NAME"></a><h2 class="nroffsh">NAME</h2>
<p class="level0">pcap_open_dead, pcap_open_dead_with_tstamp_precision - open a fake pcap_t for compiling filters or opening a capture for output <a name="SYNOPSIS"></a><h2 class="nroffsh">SYNOPSIS</h2>
<p class="level0"><pre class="level0">
&#35;include &lt;pcap/pcap.h&gt;
pcap_t *pcap_open_dead(int linktype, int snaplen);
pcap_t *pcap_open_dead_with_tstamp_precision(int linktype, int snaplen,
&nbsp;   u_int precision);
</pre>

<p class="level0"><a name="DESCRIPTION"></a><h2 class="nroffsh">DESCRIPTION</h2>
<p class="level0">
<p class="level0"><span Class="bold">pcap_open_dead()</span> and <span Class="bold">pcap_open_dead_with_tstamp_precision()</span> are used for creating a <span Class="bold">pcap_t</span> structure to use when calling the other functions in libpcap.  It is typically used when just using libpcap for compiling BPF code; it can also be used if using <a Class="bold" href="./pcap_dump_open.html">pcap_dump_open</a>, <a Class="bold" href="./pcap_dump.html">pcap_dump</a>, and <a Class="bold" href="./pcap_dump_close.html">pcap_dump_close</a> to write a savefile if there is no <span Class="bold">pcap_t</span> that supplies the packets to be written. 
<p class="level0"><span Class="emphasis">linktype</span> specifies the link-layer type for the <span Class="bold">pcap_t</span>. 
<p class="level0"><span Class="emphasis">snaplen</span> specifies the snapshot length for the <span Class="bold">pcap_t</span>. 
<p class="level0">When <span Class="bold">pcap_open_dead_with_tstamp_precision()</span>, is used to create a <span Class="bold">pcap_t</span> for use with <span Class="bold">pcap_dump_open()</span>, <span Class="emphasis">precision</span> specifies the time stamp precision for packets; <span Class="bold">PCAP_TSTAMP_PRECISION_MICRO</span> should be specified if the packets to be written have time stamps in seconds and microseconds, and <span Class="bold">PCAP_TSTAMP_PRECISION_NANO</span> should be specified if the packets to be written have time stamps in seconds and nanoseconds.  Its value does not affect <a Class="bold" href="./pcap_compile.html">pcap_compile</a>. <a name="SEE"></a><h2 class="nroffsh">SEE ALSO</h2>
<p class="level0"><a Class="bold" href="./pcap.html">pcap</a>(3PCAP), <span Class="bold">\%pcap-linktype</span>(7) <p class="roffit">
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